Manufacture of azo dyestuffs.



UNITED STATES PATENT OFFICE.

HERBERT LEVINSTEIN AND MAX WYLER, 0F BLACKLEY, MANCHESTER, ENGLAND,

ASSIGNORS TO LEVINSTEIN LIMITED, OF BLACKLEY, MANCHESTER, ENGLAND, A

LIMITED LIABILITY COMPANY.

MANUFACTURE OF AZO DYESTUFFS.

Specification of Letters Patent.

1,024,794. Patented Apr. 30, 1912. No Drawing. Application filed.October 18, 1910. Serial No. 587,700.

To all whom it may concern: The following is an example of how this Beit known thatwe,HERBERTLEVINSTEIN, invention may be carried into effect:14.3 M. Sc, Ph. D., a subject of the King of parts of beta naphthylaminare diazot-ized by Great Britain and Ireland, and MAX \VYLER, means of30 parts of 80% hydrochloric acid Ph. D., a citizen of the SwissRepublic, both and 6.9 parts of nitrite of soda in the usual id nt iBlackl y, M h ter in the manner. The diazo solution is then pouredcounty of Lancaster, England, have ininto a solution containing 32.6parts of the vented new and useful Improvements in the urethane ofQ-amino-5-naphthol-7-sulfonic Manufacture of Azo Dyestuffs, of whichacid and 20 parts of sodium carbonate. the following is a specification.After stirring for 6 hours the mass is heated This invention relates tonew monoazo 7 C. and the dyestuff is thrown out of dyestuffs dyeingcotto directly witho t a solution with the addition of salt, filtered,mordant of the following general formula lzllesie%a nd ggiedd Afterk')grindifig tge new es u is 0 a1ne as a rowms re owdgr possessing anexcellent affinity for cot- Bon, and whiloh dyes unpnordanted cottonirect in scar et shades o goodfastness to R N'N/\\l/\/ light and fast todilute alkalis and mineral OH acids It dissolves in water to ayellow-red where R represents a substituted or unsub- Solutlon fromWhlch a red fi09c u1ent P 1 Stituted benzene or naphthalene ring tateseparates out on the addltion OIE SOdIUIH The new dyestuffs are producedby comcarbons/9e- P f d1SsO1V e$ 111 9 bining a diazo compound with theurethane CGDtI'FLtQd Sulfuric. acld to a brlght Vlolet of2.5-amidonaphthol-7-sulfonic acid of the e e from Whlch a redHOG/011E111? P fonowing formula clpitate separates out on the addltionof water.

\fi Other suitable diazo compounds than that I I obtained from betanaphthylamin in the above example may be used, as, for example thosetabulated below Am. teases: ea erness: arenas, tiraaraaizaa gggggsolution. bonate. sulfuricacid. solution.

Paraxylidin Brickred... YellowrecL. Yellow red; flocculent Blue red....Brick red; flocculent Yellow red.

precipitate. precipitate. Alphanaphthylamin... Darkgreen. Bluered...Bluered;flocculentpre- Brightblue. Red; flocculent precipi- Blue recLParamidoacetanilid.... Dark red.. Cherryred" Ufii: ii e d Brightred.Brgiigi; fiocculent pre- Scarlet. Benzoylparaphenylene- Dark red...Cherryred. Red; fiocculentprecipi- Blueredui. R il b i'b wn; flocculentRed.

'amin. bate. precipitate.

What we claim as our invention is: l. The process of producing monoazodyestuffs of the general formula where R represents an aromatic substit-15 uent by combining a diazo compound with the urethane of2.5-amidonaphtho1-7-sulfonic acid, substantially as herein beforedescribed.

2. New monoazo dyestuffs having the general formula Witnesses:

JOHN OCoNNELL, ROGER B. KNoTT.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

